Currently 2G (GSM), 2.5G (GPRS) and 3G (UMTS/UTRA) mobile or cellular telecommunications networks co-exist. Mobile terminals provide continuous to service while moving from a 2G (which term hereinafter includes 2.5G) coverage area to a 3G coverage area of a network.
A development of 3G mobile telecommunications is “evolved” UTRA or E-UTRA, also referred to as SAE (System Architecture Evolution)/LTE (Long Term Evolution). It is desirable for mobile terminals to provide continuous service also when moving from an LTE coverage area to a 3G or 2G coverage area.